Procedural Forest Generation
SEN (森), the Chinese Character of "forest", is the name of this procedural terrain generator. By taking an image as input, this generator is able to create a forest based on its RGB color channels, with each one of them deciding the base height, the noise frequency, and forest density. All these information are stored in the vertices of the base terrain mesh.
After the mesh is created, the generator will plant trees according to the density information around each vertex. These trees are generated using L-system.
What's nice about the terrain is that it can be very stylized or natural based on the image input, while it is guaranteed to be playable, meaning that players can always walk inside the map and feel like an organic environment.
Below are some sample maps: